Project Summary Simulation training is unique in its ability for repetitive practice of a wide variety of scenarios and to reflect on performance without jeopardizing a patient?s safety. Medical simulation provides a controlled setting with step-wise skills progression, utilizing continuous feedback and assessment aiming at the ultimate goal of skills transfer to clinical competence. Surgical skills simulators have been successful in bridging gaps of the current training model; however, these simulators fall short of offering a complete operative experience. Operative exposure with live patients still remains the vanguard of hands-on clinical training. Under supervision and guidance, training surgeons inherently practice and refine skills on patients during residency, exposing them to unnecessary risks. To enhance the efficiency, safety and comprehensiveness of surgical training, we propose to develop inanimate models utilizing novel concepts in 3D printing technology. We have engineered a model to simulate a partial nephrectomy that replicates human anatomy, functionality (i.e. bleeding) and pathology. Through this model, comprehensive procedural training and competence can be achieved prior to operative exposure. We plan to validate this models by comparing several clinical metrics in experienced surgeons and trainees. We will also validate the physical realism of this model by testing their mechanical properties in comparison to those of human tissue.